Originally Posted by nrgtrakr
Another potentially goofy axle question ...
Supposedly when a torsion axle is loaded (bearing weight, as in under a trailer holding the trailer up) the rubber inside eventually takes a "set", or ~sags~ from the weight. Which in turn gives us reason to change them.
But what happens if the axle is not loaded? The tires are hanging down dangling thier toes in the air.
What effect (if any) would unloading an axle that has taken a set have on the set? Visualize axle CPR, or occupational therapy.
Would giving the axle a vacation prolong its life?
Or would the torsion rubber inside freak out and break causing the wheels to fall to the ground or worse while towing?
Torsion axle rubber rods, last about 25 years, but only if they are some what frequently used, like 2 to 3 times a year or more. If they are not exercise, by movement, then the rubber rods will most likely solidify.
However, if the entire weight is removed from the axles, when the trailer will be in storage for a reasonable period of time, then the rubber rods will last much longer. How much longer is not known, but information as to a longer life, if treated with zero load, says perhaps another 5 to 10 years. But that is engineering points of view, and estimates, with very little feedback. However, at least in theory, there is some truth to that opinion.
Once the rubber rods have taken a set, nothing short of replacement will correct that issue. When removed old axles are examined, the torsion arm never moves, even after a couple of years.
Torsion axles provide a soft ride for the trailer, which is a must, but not forever. Torsion axles are a great suspension system, but they do have a limited life. Twenty five years, and they are done.